Methods for reducing gastric volume

ABSTRACT

The present invention involves new interventional methods for reducing gastric volume, and thereby treating obesity. The procedures are generally performed laparoscopically and may generally be described as laparoscopic plication gastroplasty (LPG) in which, after obtaining abdominal access, spaced apart sites on a gastric wall are engaged, approximated and fastened to create one or more tissue folds forming one or more plications projecting into the gastrointestinal space. The serosal tissue may optionally be treated during the procedure to promote the formation of a strong serosa-to-serosa bond that ensures the long-term stability of the tissue plication. These procedures are preferably carried out entirely extragastrically (i.e. without penetrating through the gastrointestinal wall), thereby minimizing the risks of serious complications.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/048,206, filed Mar. 13, 2008, which claims priority under 35 U.S.C.§119(e) to U.S. Provisional Patent Application No. 60/894,626 filed Mar.13, 2007. These priority patent applications are incorporated herein byreference in their entireties.

FIELD OF THE INVENTION

The present invention relates generally to methods and devices forreducing the volume of a hollow body organ, such as gastric volume. Oneapplication of methods and devices of the present invention is treatingobesity in a patient by effectively reducing the functional volume ofthe stomach.

BACKGROUND AND DESCRIPTION OF THE PRIOR ART

Obesity is rapidly reaching epidemic proportions in developed societiesworldwide. There are currently over 1 billion overweight peopleglobally, with 300 million of these people considered clinically obese.In the United States alone there are more than 50 million obese adults,and the numbers are expected to increase by more than 50% in the nextdecade. Morbid obesity (i.e. obesity in which there are secondarycomplications such as hypertension, diabetes, coronary artery disease,stroke, congestive heart failure, orthopedic problems and pulmonaryinsufficiency) not only affects quality of life, but also shortens lifeexpectancy and costs the health care industry billions of dollarsannually.

Interventional procedures and associated medical devices for treatingmorbid obesity in patients are well known in the art. In general, theseinterventional procedures promote weight loss by either (a) gastricrestriction or volume reduction, (b) malabsorption, or (c) a combinationof the foregoing. Gastric restriction or volume reduction methodspromote weight loss by limiting the amount of food intake (i.e. thepatient eats less), either due to physical space limitation or byinducing a feeling of early satiety in the patient. Malabsorptionmethods promote weight loss by limiting the uptake of nutrients (i.e.the patient digests less of what is eaten), usually by removing orbypassing a portion of the gastrointestinal (GI) tract.

Among the earliest interventional procedures directed at promotingweight loss were variations of the jejuno-ileal bypass developed in the1950s. This surgery effectively bypasses the small intestine and istherefore a strictly malabsorption procedure, which poses serious risks.The bilopancreatic diversion procedure, which combines bypass of most ofthe small intestine with a partial gastrectomy, is a combined volumereduction and malabsorption procedure that was developed in effort toreduce these risks, but it too had complications and its success waslimited.

Roux-en-Y gastric bypass surgery is a commonly performed bariatricprocedure, especially in the US. It was originally performed as an openinterventional procedure, but it is now routinely performedlaparoscopically. This procedure utilizes interventional stapling andcutting devices to form a small stomach pouch, bypassing the lower partof the stomach, and creates a Roux-en-Y limb to attach the jejunum tothe pouch. The Roux-en-Y procedure is predominantly a volume reductionmethod (the stomach pouch is typically ˜25 cc in volume), although thereis a significant malabsorption component.

Despite the proven efficacy of the Roux-en-Y procedure in terms ofachieving weight loss, and the recent laparoscopic improvements thathave reduced the associated interventional risks, it remains a highlyinvasive procedure with substantial rates of morbidity. The rate ofinterventional mortality may be as high as 1%, and known complicationsinclude frequent pulmonary morbidity and anastomotic leaks that can belife threatening. Furthermore, the malabsorption component of theRoux-en-Y procedure can negatively affect health because of reducedvitamin uptake, and the long-term consequences of malabsorption are notyet fully understood.

A variety of other interventional procedures have also been developedinvolving the use of interventional stapling to bring together andfasten opposing walls of the stomach in order to reduce its volume. Mostinvolve malabsorption to a greater or lesser extent, depending on theprocedure. Examples of such procedures include the horizontalgastroplasty (HG) and vertical banded gastroplasty (VBG), as well asmore recent variations such as the Magenstrasse and Mill (M&M) andlaparoscopic sleeve gastrectomy (LSG) procedures that involve not onlystapling, but cutting away and removal of the unused stomach portion,leaving behind a reduced volume tube or sleeve running more or lessparallel to the lesser curvature between the esophagus and the pylorus.Surgically inserted artificial sleeves that longitudinally traverse thestomach may achieve similar effective volume reductions whilesignificantly increasing malabsorption. In any case, weight loss resultsachieved with these procedures may sometimes approach those of theRoux-en-Y, however these procedures are not easily performed, aredifficult if not impossible to reverse, and still suffer from risks ofserious complications, most frequently related to failure or leakage ofthe staples, which can lead to dangerous infections and even death.

An alternative minimally invasive procedure recently growing inpopularity involves the laparoscopic placement of an adjustable siliconering around the upper portion of the stomach, thereby creating a small(e.g. 50-120 cc) pouch. The LAP-BAND® is one such commercially availablerestrictive device that, after placement, induces a feeling of earlysatiety in the patient. Although considerably less invasive than theRoux-en-Y procedure, and potentially reversible, significantly lessweight loss has been observed with laparoscopic banding. This procedurealso suffers from a variety of limitations and shortcomings. Forexample, because the laparoscopic band does not actually reduce thevolume of the stomach, some patients report a feeling of nearly constanthunger. Additionally, long-term complications of the laparoscopicbanding procedure may include tissue erosion, slippage of the band,infection, or lack of effectiveness, frequently requiring removal of theband after a period of time.

Another less invasive alternative to the above-mentioned procedures isthe intragastric balloon. The intragastric balloon is an inflatabledevice that is deployed within the stomach, thereby displacing a knowninternal volume. The advantages of this method are that it is minimallyinvasive, involves no malabsorption component, and requires no stapling,permanent reconfiguration or removal of tissue. While the correlationbetween apparent stomach volume reduction and weight loss is wellestablished by the intragastric balloon method, the weight loss achievedis typically considerably less than with Roux-en-Y. Furthermore, unlessit is surgically fastened to the stomach wall, the balloon is freefloating and frequent complications such as obstruction, mucosalerosion, nausea, vomiting and pain have been documented, with the resultthat intragastric balloons are usually removed within 6 months afterinitial placement.

In effort to develop even less invasive devices and procedures, morerecently there has been considerable interest in various transoral (ortransesophageal) endoscopic approaches for reducing stomach volumeentirely from within the gastrointestinal lumen, without the need forabdominal incisions. In general, these approaches involve advancing anendoscope down the patient's esophagus and into the stomach, wherebyvarious tools are then used to manipulate and reconfigure the stomachtissue in order to create one or more divisions or internal folds (alsoknown as plications) within the stomach wall. To securely hold thedivisions or plications so formed, some form of sutures, staples,anchors, or other similar securing means are placed transesophageallythrough the stomach walls, and sophisticated endoscopic tools have beendeveloped for such purposes. Tissue approximation and fixation devicesfor use in endoscopic procedures are described, for example, in U.S.Patent Publications 2004/0215216, 2007/0112364, 2005/0080438. Many othertypes of endoscopic tissue approximation and fixation devices andfasteners are also known in the art.

While quite promising, endoscopic approaches for reducing stomach havevarious limitations and shortcomings. For example, they must beperformed by highly skilled endoscopic surgeons and involve the use oflarge, complicated endoscopic devices that require specialized trainingto deal with the restricted access and small working space. In order toaccess the stomach internally, devices must be passed down the patient'sesophagus, accruing a substantial risk of perforating the esophagus andinjuring adjacent organs. In addition, capturing and manipulating thetissue layers and accurately applying the securing means during atransesophageal procedure is not only difficult but also hazardous, dueto the significant risk of accidental injury to other organs, bleeding,etc., when piercing (intentionally or accidentally) the stomach wall.Because there is no extragastric visualization in these procedures,there is no advance warning of a developing life threatening situationthat may require a rescue operation.

The stomach wall is comprised of four main tissue layers. The mucosallayer is the innermost tissue layer, adjacent a submucosal connectivetissue layer. The submucosal connective tissue layer interfaces with themuscularis layer, and the serosal layer covers the exterior(extragastric) surface. Prior art gastric reduction procedures involvingtissue reconfiguration from inside the stomach require the placement ofsutures, staples, or anchors during surgery to hold the reconfiguredtissue in place strongly enough to sustain the tensile loads imposed bynormal movement of the stomach wall during ingestion and processing offood. Because the mucosal and submucosal connective tissue layers arerelatively weak and prone to elastic stretching during digestion, thesecuring means generally penetrate the stomach wall to engage at leastthe muscularis layer. For this reason, the prior art securing means aregenerally transgastric, passing one or more times completely through thestomach wall.

Proper use and placement of fasteners that penetrate the gastric wall ischallenging and concentrates significant forces over a small surfacearea of mucosal tissue, thereby potentially causing the suture, stapleor anchor to leak or tear through the tissue, with potentiallydisastrous consequences. It is well known that the fasteners used inthese procedures frequently migrate, dislodge or even completelydisappear over time, resulting in partial or complete failure tomaintain the gastrointestinal volume reduction, as well as possiblecomplications. These are significant limitations and shortcomings ofprior art bariatric procedures involving tissue reconfiguration.

Previously known interventional procedures for treating obesity throughgastrointestinal volume reduction or malabsorption thus involve numerousrisks, including life-threatening post-operative complications (e.g.internal bleeding, infection), and long-term problems such as diarrhea,vitamin deficiency, electrolytic imbalance, unpredictable orinsufficient weight loss, and gastrointestinal reflux disease (GERD).Given the above noted shortcomings, limitations and risks of prior artprocedures, it is apparent there remains a need for safe,easy-to-perform and effective interventional procedures for reducinggastric volume, as well as for devices enabling such procedures.

SUMMARY OF THE INVENTION

The methods and devices of the present invention represent a newapproach for reducing gastric volume, and thereby treating obesity andother disorders of the gastrointestinal tract, that is safe, effective,and overcomes many shortcomings and limitations of prior art procedures.In general, methods of the present invention involve reconfiguring aportion of the gastrointestinal tract (e.g., stomach wall) from theabdominal space, by contacting external tissue surfaces and drawing themtoward one another to form one or more tissue invaginations, thenapproximating the shoulders of the extragastric tissue forming theinvagination to form a tissue fold or plication, and then securing theshoulders of the extragastric tissue forming the plication to maintain apermanent plication. In preferred embodiments, the extragastric tissueis approximated such that external tissue surfaces abut one another toform the tissue plication, which extends into the internal gastricspace. One or more plications may be formed to effectively reduce thecircumference, and thereby cross-sectional area and volume, of thegastrointestinal lumen. One of the advantages of this procedure is thatthe gastric volume is reduced without reducing the mucosal surface areainvolved in digestive absorption. In a preferred embodiment of thepresent invention, the portion of the gastric tissue that isreconfigured, according to the procedure described above, is theanterior surface or anterior wall of the stomach, which is readilyaccessible from the intra-abdominal space. In another preferredembodiment of the present invention, which may allow for even greatergastric volume reduction, the portion of the gastric tissue that isreconfigured includes both the anterior surface and posterior surface ofthe stomach.

The methods of the present invention may be carried out using openinterventional procedures, which are useful, for example, to penetratethe abdominal space and obtain access to difficult or remote regions ofthe abdomen and gastrointestinal tract, such as the stomach.Alternatively, however, abdominal access to the gastrointestinal tract(e.g., stomach) is provided using conventional laparoscopic proceduresthat involve relatively minimal penetration of the abdominal space.Minimally invasive non-laparoscopic methods may also be used (i.e.wherein access to the abdominal cavity is achieved without establishinga pneumoperitoneum via insufflation) to access the external surface(s)of the gastrointestinal tract. Numerous methods for accessing theinternal abdominal space, and for monitoring intra-abdominalinterventions (e.g., imaging and visualizing the intra-abdominal spaceand intervention) are known and may be used in conjunction with methodsof the present invention.

According to one embodiment of the present invention, a method forreducing gastric volume comprises obtaining access to an externalsurface of the gastrointestinal tract (e.g. stomach); invaginating andapproximating the wall of the gastrointestinal tract from its externalsurface to create at least one plication therein; and fastening surfacesof the approximated gastrointestinal wall to one another to secure theplication(s). According to another embodiment, a method for reducinggastric volume comprises obtaining access to an external surface of thegastrointestinal tract (e.g., stomach); invaginating and approximatingthe wall of the gastrointestinal tract from its external surface bydrawing external surfaces of the gastrointestinal tract toward oneanother to form a plication extending into the interior space of thegastrointestinal tract; and fastening the approximated surfaces of thegastrointestinal wall to one another to secure the plication(s). Thismethodology provides a significant reduction in the internal volume ofthe gastrointestinal tract (e.g., stomach) without reducing the interiorwall surface available for digestion and nutrient absorption.

The exterior serosal layer and adjacent muscularis layers of thegastrointestinal tract have relatively more strength than the submucosaland mucosal layers. In certain embodiments of methods of the presentinvention wherein external surfaces of the gastrointestinal wall areapproximated to form a plication projecting into the internal space ofthe gastrointestinal tract, fastening of the approximated portions ofthe gastrointestinal wall is accomplished by penetrating fewer than allof the layers of the gastric wall. In preferred embodiments, fasteningof the approximated portions of the gastric wall is accomplished bypenetrating at least the thin, tough serosal layer covering the exteriorof the gastrointestinal lumen and, optionally, the serosal andmuscularis layers, without penetrating the submucosal and mucosal layersof the gastric wall. In these embodiments, the intragastric space is notbreached during the procedure, and the mucosal layer of thegastrointestinal tract remains intact. This is advantageous not onlybecause it simplifies the procedure, but also because it avoids avariety of known complications arising from prior art procedures thatmay result when transgastric methods are employed that puncture, damageor otherwise compromise the mucosa during the intervention. Thus,according to another embodiment, a method for reducing gastric volumecomprises obtaining access to an external surface of thegastrointestinal tract (e.g. stomach); invaginating and approximatingthe wall of the gastrointestinal tract from its external surface to forma plication extending into the interior space of the gastrointestinaltract; and fastening approximated surfaces of the gastrointestinal wallto one another without penetrating all layers of the gastric wall tosecure the plication(s). In one embodiment, the surfaces of thegastrointestinal wall are fastened to one another using fasteners thatpenetrate at least the serosal layer and preferably the serosal andmuscularis layers of portions of the gastrointestinal wall forming theplication.

Additional embodiments of methods of the present invention, disclosed indetail below, incorporate additional features for the purpose ofimproving the safety and effectiveness and/or reducing the complexityand cost of the procedure. For example, in one embodiment of methods ofthe present invention, immediately prior to, or contemporaneously withthe above mentioned invaginating and approximating steps, serosal tissueon surfaces of the gastrointestinal wall that adjoin to form theplication is treated to promote bonding or adhesion of adjoining tissuelayers within the plication. In one embodiment, bonding of adjoiningtissue layers within the plication is accomplished by disrupting theserosal tissue and promoting a healing response therein. In onepreferred embodiment, a serosal tissue treatment that involves serosaltissue disruption and/or promotion of the formation of aserosal-to-serosal bond is provided over substantially thegastrointestinal surface area involved in forming the one or more tissuefolds.

It is known that serosal tissue is capable forming strong adhesions toitself, or adjacent tissues, following inadvertent disruption of ordamage to the serosal tissue that occurs during surgery. Typically, suchadhesions are considered an undesirable and sometimes dangerouscomplication of abdominal surgery, and avoiding inadvertent damage tothe serosa to minimize the formation of adhesions is an important goalduring abdominal interventions. In contrast, in methods of the presentinvention, serosal tissue disruption and formation of the consequentadhesions may be optionally and intentionally promoted on targetedsurface areas of the gastrointestinal lumen. When combined with theinvaginating and approximating methods of the present invention, it hasunexpectedly been discovered that serosal adhesions can be usedbeneficially for the purpose of providing a supplementary or evenprimary securing means for the gastrointestinal reconfiguration.According to the present invention therefore, serosal tissue on surfacesof the gastrointestinal wall that form the plication may be treated todisrupt the serosal tissue and promote a healing response for thepurpose of selectively promoting the formation of a serosa-to-serosabond across the approximated tissue boundary within the gastrointestinalplication.

A strong serosa-to-serosa bond is typically formed after a relativelybrief period of time (e.g. approximately 7 days after surgery). Onceformed, this serosa-to-serosa bond is sufficiently strong tosubstantially resist the separation forces generated by the stomachduring ingestion and digestion, and ensures the long-term integrity ofthe plication. The formation of a strong serosa-to-serosa bond in thegastric plication of the present invention significantly improves thedurability and lifespan of the plication, and consequently of thegastric reduction, and offers a significant improvement compared to the(solely) mechanical fastening methods used in tissue approximation andplication in the prior art. Thus, in the present invention, thefasteners used during the intervention to initially secure the tissuefold serve as the sole structural support for securing the plicationonly during the brief healing phase following surgery. Following itsformation, the serosa-to-serosa bond may provide the primary structuralsupport for securing the plication, and the fasteners initially placedto secure the plication may be removed, absorbed or, more typically,left in place within the patient to provide additional support for theplication.

In contrast to Roux-en-Y or other gastrectomy procedures involvingstapling, it should be pointed out that the method of the presentinvention does not require cutting, transection, anastomosis, or removalof any gastrointestinal tissues from the body. It is therefore possiblethat the gastric reduction accomplished during this procedure isinterventionally reversible. For example, if at a later date thesurgeon/patient elects to reverse the gastric reduction, it is possibleto substantially restore the original gastrointestinal configurationusing a simple and safe procedure wherein the plication is substantiallyeliminated by removal of any remaining implanted securing means,followed by dissection of the serosa-to-serosa bond along the originalline of tissue approximation, and subsequent localized treatment toprevent further formation of adhesions during post-operative healing.

A variety of novel devices, tools and systems are provided herein thatenable a medical professional to engage and approximate soft bodytissues during an interventional procedure, more safely and convenientlythan possible using the prior art instruments. These inventive devices,tools and systems are useful for, among a variety of other possibleinterventional purposes, performing gastric reduction procedures byinvaginating and approximating the wall of the gastrointestinal tractfrom its external surface to create at least one plication therein; andfastening surfaces of the approximated gastrointestinal wall to oneanother to secure the plication(s).

Gastric reduction methods of the present invention are performed in theabdominal cavity and involve contacting and manipulating thegastrointestinal tract from its external surface. The methods aretypically accomplished using minimally invasive laparoscopic techniques,and the devices and systems of the present invention are thereforegenerally intended to be used in connection with laparoscopictechniques. However, any technique that provides access to theintra-abdominal space and, particularly, the exterior surface of thegastrointestinal tract may be used, including natural orificetransluminal endoscopic surgery (NOTES) techniques and other minimallyinvasive non-laparoscopic techniques.

In one embodiment, a specialized device is provided for carrying out thetissue invagination and approximation steps; another device mayoptionally be provided for disrupting and/or promoting the bonding ofserosal tissue, and yet another device may be provided for securing thetissue plication(s). A device for invaginating and approximating gastrictissue of the present invention preferably comprises a tool having anactuation mechanism (generally on or in proximity to a handle)manipulable by an operator, at least one extendible member, and at leasttwo tissue engagement mechanisms. Tissue engagement mechanisms aregenerally provided at or in proximity to the distal end(s) of the deviceor extendible member(s), but may be provided at other locations. In oneembodiment, the approximation device comprises at least one tissueengagement mechanism provided in association with a device shaft that isinserted at the site of the intervention, and another tissue engagementmechanism provided in association with an extendible member. In thisembodiment, tissue is approximated by engaging tissue at two spacedapart locations using the tissue engagement mechanisms and then movingthe extendible member and the device shaft relative to one another toapproximate the engaged tissue.

According to another embodiment, the approximation device of the presentinvention comprises at least one tissue engagement mechanism provided inassociation with each of at least two extendible members. The extendiblemembers are adjustable by the operator between an insertion (collapsed,pre-deployed) condition, in which they may be inserted into theabdominal space, and an expanded (extended, deployed) condition, inwhich the associated tissue engagement mechanisms are separated andpositioned to engage two portions of tissue spaced apart from oneanother. The extendible member(s) are also adjustable by the operator,by means of an actuation mechanism, following engagement of the twoportions of tissue to draw together, or approximate, the two portions oftissue engaged by the tissue engagement mechanisms. The tissueengagement mechanisms are furthermore manipulable to release engagedtissue, and the extendible members are manipulable to reposition themembers in a low profile, collapsed condition for withdrawal of thedevice from the abdominal space. Thus, in operation, the distal portionof the tissue invagination and approximation device is positioned in theabdominal space; a control feature is actuated by the operator to adjustthe extendible members from a low-profile, collapsed condition to adesired extended condition; and the tissue engagement mechanisms arepositioned to engage the exterior surface of spaced-apart portions ofthe gastrointestinal tract (e.g., stomach); a control feature isactuated by the operator to draw the tissue engagement mechanismstogether and approximate the two engaged portions of tissue; theengagement mechanisms are disengaged from the tissue; and afterrepeating the above steps any desired number of times, the extendiblemembers are collapsed and the device is withdrawn from the abdominalcavity.

In one embodiment, the device for invaginating and approximatinggastrointestinal tissue has a selection feature that allows the medicalprofessional to select the degree of separation of the extendiblemembers in the expanded condition, and thereby select and controlplacement of the tissue engagement mechanisms and the overall size ofthe one or more tissue folds to provide a desired degree of gastricreduction. In another embodiment, a variety of interchangeable tools maybe provided, allowing the operator to select approximation toolsproviding the desired placement of tissue engagement mechanisms and,consequently, the overall size of the tissue fold(s).

Another tissue invagination and approximation device of the presentinvention comprises a tool having at least two extendible membersadjustable between a collapsed insertion condition and an extendedoperating condition, and additionally comprising at least one tissueinvagination structure arranged and adjustable along an axis to contactand invaginate tissue located generally at a midline between the tissueportions engaged by the tissue engagement mechanisms. The tissueinvagination structure is preferably axially adjustable between awithdrawn insertion condition in which it does not extend substantiallybeyond the terminal ends of the extendible members and an invaginating,projected condition, in which the tissue invagination structure projectstoward the midline of the tissue surface engaged by the tissueengagement mechanisms. In one embodiment, the axial movement of thetissue invagination structure may be coordinated with the extension ofthe tissue engagement mechanisms such that, following engagement of twospaced apart portions of tissue, the tissue invagination structure isextended to contact and invaginate tissue as the approximation membersare drawn together to approximate the two spaced apart tissue portions.A selection feature may allow the medical professional to select thedegree of extension of the invagination structure, thereby controllingthe overall size of the tissue invagination and plication, and providinga desired degree of gastric reduction.

In yet another embodiment, a serosal treatment device may be providedand used separately from or in coordination with the tissueapproximation and invagination device. A serosal tissue treatmentdevice, in one embodiment, is adapted to disrupt serosal tissue lyingbetween spaced apart tissue surfaces engaged by the approximatingmembers to promote healing and formation of a serosal-to-serosal bondbetween serosal tissue surfaces contacting one another in the plicationformed during the tissue approximation. The serosal treatment device mayutilize one or more mechanical structures, such as a discontinuous or anon-smooth surface structure, to disrupt serosal tissue and therebypromote serosal tissue adhesion. Additionally or alternatively, theserosal treatment device may be operated to facilitate application oradministration of an agent that promotes serosal tissue disruptionand/or healing in serosal-to-serosal bonds, or to administer a tissuebonding agent that promotes serosal-to-serosal tissue bonds. The serosaltreatment device may incorporate an alternative modality for serosaltissue treatment, e.g., by application of heat, RF radiation,ultrasound, electromagnetic radiation, or other types of radiatingenergy. In one embodiment, the serosal tissue treatment device may beintegrated with the approximating members and/or the tissue invaginationstructure, as described more fully below.

A separate tissue securing or fastening device may be provided forfastening the two adjacent portions of approximated tissue to oneanother to secure the plication. Suitable devices, such as suturing,stapling and other types of mechanical tissue fastening devices are wellknown in the art. The tissue fastening device, in one embodiment, is amulti-fire device that is capable of administering multiple fasteners,in multiple positions along a line of approximated tissue, withoutrequiring removal from the abdominal space. Various types of fastenersand fastening devices may be used, as described more fully below.

In another embodiment, an integrated device may be provided for carryingout the tissue invagination and approximation steps, and for optionallytreating serosal tissue in the invaginated tissue, while a separatedevice may be provided for securing the tissue plication. Thisbeneficially eliminates the need for at least one laparoscopic incisionand trocar during the procedure. In yet another embodiment, a singlemulti-functional device is provided that comprises tools capable ofinvaginating and approximating tissue, optionally treating the serosaltissue to promote a healing response, and for securing the tissue foldto produce the plication. In this embodiment, a single minimallyinvasive laparoscopic device is provided, thereby minimizing the numberof trocars needed to complete the procedure. For example, assuming oneaccess port is needed for the video camera and one is needed for agrasper, liver/organ manipulator, dissector, or other tissuemanipulation device, the procedure may be completed using only 3trocars. In another embodiment, the single integrated minimally invasivelaparoscopic device may be optionally configured having one or moreextra service channels through which the camera and other tissuemanipulation devices may be inserted, thereby allowing the entiregastric reduction intervention to be completed using only a singleaccess port. In comparison, 5 or more laparoscopic incisions arecommonly needed for the Roux-en-Y procedure. Using a multifunctionaltool of the present invention, the gastric reduction procedure is lessinvasive, requires less time to complete and therefore reduces the risksattendant any intervention, speeds patient recovery, and reduces theoverall cost of treatment.

Other embodiments of medical devices of the present invention furtherincorporate novel tool configurations, detailed below, that enable andsimplify the steps of securing the one or more tissue folds created inorder to produce the one or more plications in the wall of thegastrointestinal tract. In one embodiment, means are provided fordelivering individual tissue anchors comprising a securing assembly. Inyet another embodiment, individual tissue anchors are reconfigured froma first state (e.g. a configuration used for delivery) to a second state(e.g. a deployed configuration). In yet another embodiment, the deployedsecuring assembly is configured to penetrate only the serosal andmuscularis tissue layers, without penetrating completely through thewall of the gastrointestinal tract.

According to the brief summary provided above, it is apparent thatmethods and devices of the present invention offer several advantagesover the prior art. For example, because the one or more gastric tissueplications produced may achieve substantial therapeutic gastricreductions, it is possible to obtain weight loss results comparable toprior art procedures using an interventional alternative that may beperformed using minimally invasive laparoscopic or non-laparoscopicabdominal access procedures, while at the same time avoiding a varietyof complications associated with malabsorption, the long-term presenceof restrictive devices within the body, leakage or failure attransgastric anastomosis or anchoring sites, permanent restructuring ofthe gastrointestinal tract, and the like. Gastric reduction proceduresof the present invention are therefore simpler, easier to perform, andsafer that prior art interventional methods. In addition, the methods ofthe present invention, which may optionally be performed substantiallyor entirely extragastrically, may be carried out by conventionallyskilled laparoscopic surgeons, requiring minimal specialized training toachieve substantial gastric volume reduction and effective weight lossresults, while significantly reducing the risk of injury or damage toneighboring organs and other complications. This is a significantadvantage compared to prior art transesophageal endoluminalinterventional methods.

While the present invention will be described more fully hereinafterwith reference to the accompanying drawings, in which particularembodiments are shown and explained, it is to be understood that personsskilled in the art may modify the embodiments herein described whileachieving the same methods, functions and results. Accordingly, thedescriptions that follow are to be understood as illustrative andexemplary of specific structures, aspects and features within the broadscope of the present invention and not as limiting of such broad scope.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 schematically illustrates an interventional method according toone embodiment of the present invention, pre-procedure (FIGS. 1A-1A3),and post procedure (FIGS. 1B-1B2).

FIGS. 2A-2E2 schematically illustrate an exemplary interventionalgastric reduction method according to one embodiment of the presentinvention.

FIGS. 3A and 3B show an organ having a plication and a cross sectionalview of a plication, illustrating securing means applied according toone embodiment of the present invention.

FIGS. 4A and 4B show an organ having two plications and a crosssectional view of the multiple plications according to one embodiment ofthe present invention.

FIGS. 5A-5F illustrate operation of a medical device according to oneembodiment of the present invention, wherein FIG. 5A shows an overview;FIG. 5B shows a close-up, distal end of the device in a collapsed state;FIG. 5C shows a close-up, distal end of the device in an extended state;FIG. 5D shows the device in an extended state following tissueengagement; FIG. 5E illustrates partial retraction of the extendiblemembers and tissue engagement mechanisms and actuation of a projectingserosal tissue treatment member during invagination and approximation;and FIG. 5F illustrates complete retraction of the extendible membersand full extension of the projecting serosal tissue treatment member toform the plication.

FIGS. 6A-6D illustrate a medical device system according to oneembodiment of the present invention, wherein FIG. 6A shows separatetools positioning; FIG. 6B shows the tissue fold created; FIG. 6C showsthe fasteners applied; and FIG. 6D shows a plurality of fasteners.

FIGS. 7A-7H illustrate a medical device according to one embodiment ofthe present invention, wherein FIG. 7A shows an overview; FIG. 7B showsthe distal end in collapsed state; FIG. 7C shows the distal end inexpanded state; FIG. 7D shows the tissue engagement; FIG. 7E shows thetissue invagination and approximation; FIG. 7F shows the tissue foldcreated; FIG. 7G shows the securing means applied, with the distal endretracted to collapsed state; and FIG. 7H shows a plurality of securingmeans.

FIGS. 8A-8E illustrate a medical device according to another embodimentof the present invention, wherein FIG. 8A shows the distal end of atissue approximation device in a collapsed state and FIG. 8B shows ahelical fastener for use in the tissue approximation device of FIG. 8A;FIG. 8C shows a tissue fold created; FIG. 8D shows the fasteners appliedand the distal end retracted to collapsed state; and FIG. 8E shows aplurality of fasteners applied.

FIGS. 9A and 9B illustrate an embodiment of the present invention,wherein FIG. 9A shows a first tissue fold created and first fastenerapplied to produce first plication; and FIG. 9B shows a second tissuefold created and a second fastener applied producing second plication.

FIG. 10A illustrates a multifunctional tool for placing helicalfasteners and FIG. 10B shows a plurality of helical fasteners applied tosecure a tissue fold and thereby produce a plication.

FIG. 11 shows another embodiment of the present invention involvingarticulation of the distal multi-functional tool assembly.

DETAILED DESCRIPTION OF THE INVENTION

Methods of the present invention provide effective reduction of thefunctional volume of the gastrointestinal tract (e.g., stomach) using anextragastric gastroplasty procedure. In this procedure, a portion of thegastrointestinal tract is reconfigured by invaginating and approximatingtissue to form one or more tissue folds, and then securing the one ormore tissue folds in order to produce one or more plications. While thefollowing detailed descriptions refer in general to reducing thefunctional volume of the gastrointestinal tract, the stomach inparticular, it should be recognized that the invaginaton, approximationand securing methods of the present invention may be used on other bodytissues and for other interventional purposes, within the scope of thepresent invention.

Gastric reduction procedures of the present invention generally accessthe gastrointestinal tract via the abdominal cavity. This is mosttypically accomplished using conventional laparoscopic techniqueswherein the patient is anesthestetized, one or more small incisions aremade through the abdominal wall, and a pneumoperitoneum is establishedby insufflation, thereby allowing the insertion of imaging devices andone or more interventional instruments through laparoscopic ports, alsoknown as trocars. Alternatively, methods of the present invention mayalso be carried out when access to the abdominal cavity andgastrointestinal tract is obtained using even less invasive,non-laparoscopic techniques. A variety of such non-laparoscopictechniques may be utilized within the scope of the present invention,typically involving grasping and lifting, or otherwise retracting theabdominal wall to create sufficient working space within the abdominalcavity, without the need for insufflation. Alternatively, the methodsand devices of the present invention may also be adapted for flexibleendoscopic use, allowing access to the abdominal cavity and externalsurface of the gastrointestinal tract to be obtained by first enteringthe body through a natural orifice (e.g esophagus, anus or vagina), thenpenetrating through the wall of an anatomical lumen into the abdominalcavity.

Once abdominal access has been obtained, the medical professionalemploys one or more cameras or other imaging devices, along with avariety of tools known in the art, to manipulate the internal organsand/or tissues to expose the region of the gastrointestinal tract ofinterest. In preferred embodiments of the present invention, at leastthe anterior portion of the stomach is exposed sufficiently to allow forits reconfiguration. This may require dissection and/or removal of atleast a portion of the omentum, and it may require lifting and/orpartial retraction of the liver, both of which are relatively simpleinterventional steps that are well known in the art. The subsequentreconfiguration and gastric reduction may then be performed, preferablyusing the devices and systems of the present invention, which aredescribed in detail below.

FIG. 1 schematically illustrates the relevant portion of thegastrointestinal tract (anterior view), both pre-procedure (FIG. 1A) andpost-procedure (FIG. 1B). To aid in the following discussion, it ishelpful to first distinguish the various anatomical structures in FIG.1A. The stomach itself lies between the esophagus 105 and pylorus 110.The anterior wall 115 of the stomach is shown, along with the fundus120, the greater curvature 125, and lesser curvature 130. Twocross-sectional views of the stomach are shown in FIG. 1A1 at X-X and inFIG. 1A2 at Y-Y. It is helpful to point out the major tissue layers ofthe stomach wall, as illustrated in FIG. 1A3. Starting intragastricallyand moving outward, the innermost tissue layer is the mucosal tissuelayer 150, then there is a submucosal connective tissue layer 152, themuscularis tissue layer 155, and the exterior serosal tissue layer 160that covers the extragastric surface of the stomach.

FIG. 1B illustrates a stomach following gastric reduction according tomethods of the present invention. As shown in FIGS. 1B1 and 1B2, thestomach now exhibits a significantly reduced cross sectional area (e.g.at X-X and Y-Y) and the functional volume of the stomach has beendecreased approximately 50% as a result of single fold 180 being placedin the anterior wall 115 of the stomach. As shown, fold 180 is locatedapproximately midway between the greater curvature 125 and lessercurvature 130, and extends approximately longitudinally from near fundus120 to near pylorus 110. As can be seen in sections X-X and Y-Y of FIGS.1B1 and 1B2, fold 180 was created by invaginating and approximating thetissue of the anterior wall 115 of the stomach so as to bring theserosal tissue layer 160 into contact with itself Fasteners are thenapplied to the tissue brought together to produce the plication in thewall of the stomach.

In a preferred embodiment of the present invention, a single fold andplication is produced in the above described manner and location, asillustrated in FIG. 1B; however, in other embodiments, two or more suchplications may be produced. Although the plication is illustrated asbeing formed approximately midway between the greater and lessercurvatures of the stomach, it will be appreciated that other areas ofthe stomach or gastrointestinal wall may be used, as may be necessarybased on individual anatomy and the surgeon's desire to achieve thetargeted functional gastric reduction, while minimizing the overallinvasiveness of the procedure. According to the present invention thefunctional volume of the stomach is preferably decreased at least 20%,is more preferably decreased at least 30%, and is most preferablydecreased at least 40%. In morbidly obese patients, a functional volumereduction of 50% or more may be achieved in order the promote thedesired excessive weight loss.

In FIG. 1B, securing means comprising a row of individual staples 185are placed substantially along the length of fold 180. As shown in FIG.1B2 at section Y-Y, staples 185 grasp tissue shoulders 195 that areformed where the opposing tissue layers of the tissue fold intersect thecircumference of the stomach. As can also be seen in section Y-Y,according to a preferred embodiment of the present invention, staples185 engage tissue shoulders 195 by penetrating only through serosaltissue layer 160 and underlying muscularis tissue layer 155, withoutpenetrating completely through the stomach wall to breach or otherwisecompromise mucosal tissue layer 150. As can also be seen in section Y-Y,according to another preferred embodiment of the present invention, theapproximated tissue surfaces within the tissue fold are configured suchthat there is substantially intimate serosal-to-serosa contact withinthe plication 190.

FIG. 2 illustrates in greater detail the intermediate steps of theprocedure, according to one embodiment of the present invention. FIG. 2Aand FIG. 2E are identical to FIG. 1A and FIG. 1B, respectively, and arerepeated for completeness. FIG. 2B, FIG. 2C and FIG. 2D are helpful toexplain other aspects of the intermediate steps. In FIG. 2B, forexample, prior to commencing with the reconfiguration portion of theprocedure, the region of interest on anterior wall 115 may be visuallyidentified, marked or mapped out to aid subsequent steps of theprocedure. For example, it may be desirable to identify and/or indicatethe target position and length of the fold centerline 202, as well asthe bounding lines 204 and 206 where the tissue will be contacted,engaged and/or secured. The location of bounding lines 204 and 206define the depth of the tissue fold to be created, as well as thesurface area of tissue that will be approximated during creation of thetissue fold. Identification, marking and/or mapping of the tissuestructures and/or locations can be carried out according to methods wellknown in the art, for example, inks, dyes, adhesives, implantable tags,clips, fasteners, radio-opaque markers, fluorescent markers, cauterizingmarks, and the like, may be used.

FIG. 2C schematically illustrates the early steps in the procedure,starting at one end of the target area (e.g. near the pylorus) andworking progressively in one direction (e.g. toward the fundus). Itshould be recognized, however, that this progression is optional, andthat it is just as feasible to start near the fundus and work toward thepylorus, to start anywhere along the length of the intended fold andwork in both directions, or any combination of the foregoing. To form atissue fold, the tissue is contacted and/or engaged at two or morelocations, and various combinations of relative motions are then used toensure the tissue is invaginated as the opposing tissue surfaces areapproximated. Examples of such combinations of relative motions includeone or more motions selected from the group consisting of pushingmotions, pulling motions, twisting motions, and shearing motions.

In FIG. 2C, for example, tissue is contacted and engaged at locations208 and 210 on opposite sides of a fold centerline location 212.Relative motion between central location 212 and the tissue contact andengagement locations 208 and 210, is represented in FIG. 2C1 by pushingforce vector 214 and pulling force vectors 216 and 218, respectively.These motions invaginate the tissue and approximate the opposing tissuesurfaces, while bringing tissue shoulders 195 toward each other forsubsequent securing. The relative motion illustrated may be achieved,for example, by holding central location 212 substantially stationaryand pulling the tissue engagement points 208 and 210, or by holding thetissue engagement points 208 and 210 substantially stationary andpushing on the central location 212, or alternatively, any combinationof pushing and pulling may be used to achieve the same effect.

After the tissue has been approximated to create the tissue fold 180 asdescribed above, and tissue shoulders 195 have been brought togetherinto proximity of one another, a tissue fastener 185 is then applied atthat location to secure the plication 190, as shown in FIG. 2D. In FIG.2D, exemplary tissue fastener 185 is schematically shown as a box-typeof interventional staple, similar in form and function to a box-typestaple known in the art of interventional skin stapling for use in woundclosure applications. However, it should be obvious to those skilled inthe art that, within the scope of the present invention, a wide varietyof mechanical elements may be used as tissue fasteners 185 for thepurpose of anchoring, fastening, holding, attaching, or otherwisesecuring tissue surfaces 180 to produce plication 190. Examples ofsuitable tissue fasteners that may be used include but are not limitedto sutures, staples, screws, tacks (e.g. U-shaped, circular and helicalfasteners), clips, hooks, clamps, t-tags, and the like. In a preferredembodiment of the present invention, tissue fasteners 185 are preferablyapplied at least directly across tissue shoulders 195 at more than onelocation along the length of tissue fold 180, more preferably at severalrelatively closely spaced locations to secure the plication.

The tissue engagement, approximation and fastening steps are repeatedany number of times as is necessary to completely form and secure theone or more tissue plications. In the example provided herein, the finalresult is shown schematically in FIG. 2E.

For convenience, the procedure may progress sequentially in onedirection along the length of the intended fold, as illustrated in FIG.2D, effectively producing the plication in a manner similar to closing azipper. However, sequential advancement is not required, and the surgeonmay use discretion in deciding where to begin and how to advance theprocedure. At each of one or more locations along the length of theintended fold, the tissue is invaginated, approximated and secured withone or more tissue fasteners before moving to the next location. In oneembodiment, a device may be provided that allows simultaneous orsequential placement of multiple tissue fasteners while the invaginatingand approximating tool is placed and held at one location.Alternatively, in another embodiment, a device may be provided thatallows placement of a single tissue fastener along a substantial length,or even along the complete length, of the tissue fold, while theinvaginating and approximating tool is held at one location.

According to one embodiment of the present invention, prior to securingthe approximated tissue to produce the one or more plications, at leasta portion of the surface area of the serosal tissue enfolded by the oneor more plications is selectively treated to promote serosal-to-serosaltissue bonding. There is a considerable body of clinical knowledgeregarding the mechanisms of abdominal adhesion formation, and a varietyof methods known to those skilled in the art may be used to selectivelytreat the serosal tissue surfaces to promote tissue adhesion of theserosal tissue layers adjoining one another inside the tissue foldforming the plication. Examples of such tissue treatments include butare not limited to mechanical disruption methods (e.g. abrasion), energydeposition methods (e.g. RF, ultrasonic, electromagnetic, and the like),methods involving treatment using liquids (e.g. chemicals,pharmaceuticals, adhesives, etc.) and methods involving treatment usingsolids (e.g. powders, films, etc.). Regardless of the tissue treatmentmethod used, an important aspect of this embodiment is that serosaltissue bonding or adhesion is promoted over a sufficiently largeinterfacial surface area across the approximated tissue boundary withinthe plication to achieve a strong and durable serosa-to-serosa bondpost-operatively.

In yet another embodiment of the present invention, additional tissuefasteners may also be optionally applied while the tissues are beingapproximated to aid in forming, stabilizing and/or providing additionalstrength to the resulting tissue plication, as well as to furtherpromote the formation of a strong serosa-to-serosa bond inside theplication. For example, as illustrated in the enlarged cross sectionalview X-X shown in FIG. 3B, in addition to outer tissue fastener 305(similar to the tissue fastener 185 described previously), one or moreadditional internal tissue fastener 310 may be applied across thecontact area of the approximated tissue surfaces within the fold whileit is being formed, such that after the plication is completed, the oneor more additional internal tissue fasteners 310 are located inside theplication for the purpose of better securing the tissue across theapproximated tissue surfaces. Additional internal tissue fastener 310may be identical to outer tissue fastener 305, being placed by the samedevice, or in an alternative embodiment, additional internal tissuefastener 310 may have a different design and/or be placed usingadditional devices. Note that additional internal tissue fastener 310also preferably penetrates only the serosal and muscularis tissuelayers. Although FIG. 3 illustrates the use of a box-type staple, as inthe case of tissue fastener 185 described previously, this embodiment ismerely illustrative and a wide variety of alternative fasteners existthat may be used for the outer tissue fastener 305 and additionalinternal tissue fastener 310, within the scope of the present invention.

In yet another embodiment of the present invention, more than one tissueplication may be produced according to the previously described methods.For a variety of reasons, it may be advantageous in some cases toproduce two or more plications. These advantages may include, forexample, allowing a greater range of effective volume reductions in thestomach to be achieved, allowing smaller laparoscopic devices to beused, allowing the surgeon more flexibility in positioning of theplications relative to the stomach or surrounding organs, for reducingthe maximum forces generated on the individual securing means, and soon. FIGS. 4A and 4B schematically show an example according to oneembodiment of the present invention in which tissue two adjacent tissuefolds 402 and 404 have been placed in the anterior wall of the stomach,running more or less parallel to one another. As can be seen in FIG. 4Bin the enlarged view of cross section X-X, tissue fold 402 has beensecured with tissue fastener 405 to produce a first plication 410,whereas tissue fold 404 has been secured with tissue fastener 415 toproduce a second plication 420. It should be obvious to those skilled inthe art that within the scope of the present invention, it is possibleto produce any number of individual and separate plications in themanner described previously, each of which plication may becharacterized individually in terms of length, depth, position, numberand type of fasteners placed, and so on, to achieve the intendedinterventional result.

Interventional Devices and Systems

Interventional devices for performing methods of the present inventionare described herein that, taken together, comprise systems of thepresent invention. The devices and systems of the present inventionprovide the ability to carry out the above described volume reductionprocedures in a safe, efficient and minimally invasive manner, which isdifficult or impossible to accomplish using prior art devices. It willbe appreciated that while the devices and systems of the presentinvention are described below with respect to their use in gastricreduction methods of the present invention, they have utility and may beused for general approximation and fastening of other types of soft bodytissues and in other types of interventional procedures as well.

In general, at least one handheld interventional instrument is providedhaving one or more integrated tool assembly(ies) adapted for placementat an interventional site, such as within the abdominal cavity, incombination with one or more actuator(s) positioned remotely from thetool assembly and providing operator control of the tool assembly(ies)during an intervention. The tool assembly is preferably capable ofengaging tissue at two or more separate locations, and then invaginatingand approximating tissue to effectively create a tissue fold between thetissue engagement locations. In one embodiment, the tool assemblycomprises at least two tissue engagement mechanisms (e.g. clamps,grippers, forceps, jaws, hooks, barbs, vacuum ports or the like, orcombinations of these mechanisms) positioned at or in proximity to thedistal end of an elongate shaft of a laparoscopic device. The tissueengagement mechanisms may be positionable by means of a remote actuator,or they may be mounted on supporting members that may be positionable toengage desired tissue sites. Using this device, the laparoscopic shaftis positioned within the abdominal cavity, and the distal end of theshaft is positioned at a first desired tissue engagement site, where atissue engagement mechanism is engaged with the tissue. The operatorthen repositions the shaft by moving it to a second location, draggingthe first engaged tissue location toward the second, and therebyapproximating the first and second tissue locations. The approximatedtissues may then be fastened to one another to secure the plicationusing fasteners applied with an independent device or an integratedassembly of the tissue approximation device.

In another embodiment, a first tissue engagement mechanism may bepositioned at the distal end of the elongate shaft of a laparoscopicdevice, while a second tissue engagement mechanism may be positioned atthe distal end of an extendible member that can be manipulated by anoperator to move away from the axis of the device shaft to position thesecond tissue engagement mechanism at a second location, remote from thedistal end of the device. The extendible member may be substantiallyrigid, or it may be flexible, or it may have both substantially rigidand flexible portions, and it may either be deployable from inside theelongate shaft of the laparoscopic device, or attached near the distalend of the shaft by mechanical means. In one embodiment, a proximal endof an extendible member is attached near the distal end of the elongateshaft using a pivot connection, a hinge connection, a flexibleconnection, or the like, that allows the extendible member to beoperatively and selectively actuated to move its distal, operating end(comprising a tissue engagement member) away from the axis of thelaparoscopic device to engage tissue. In operation, the distal end ofthe shaft of the laparoscopic device is first positioned at a desiredtissue surface and the tissue is engaged at a first site. The extendiblemember and its associated tissue engagement mechanism is then deployed,extending away from the axis of the shaft to independently engage tissueat a second location. The extendible arm and its associated tissueengagement mechanism is then retracted, under control of the operator,and the second engaged tissue location is drawn in toward the axis ofthe shaft and thereby approximated adjacent the first engaged tissuesite. An invaginated tissue fold projecting away from the distal end ofthe device and into the gastrointestinal space is created as the twotissue sites are drawn together and approximated.

In other embodiments, described in detail below, two or more suchextendible members are provided on an interventional device, eachextendible member having at least one tissue engagement mechanism,generally (but not necessarily) positioned at its distal end, such thatthe engagement of tissue at multiple separate locations can beaccomplished without requiring the shaft of the laparoscopic deviceitself to contact the tissue surface. The extendible members may beactuated and positioned separately and independently of one another, orthey may be actuated and positioned simultaneously and in coordinationwith one another. Operation of this type of device involves deployingeach of the extendible members and their associated tissue engagementmechanisms, independently or in coordination, to contact the tissueengagement mechanisms at two locations on the tissue, then approximatingthe engaged tissue to form an invaginated tissue fold by moving at leastone of the extendible members toward the other and, in some embodiments,by moving multiple extendible members toward a central location, therebyapproximating the engaged tissue substantially near the distal end ofthe device (or along a longitudinal axis extending therefrom).

Another embodiment that provides an alternative to using two or moreextendible members to engage tissue involves the use of tethers. In thiscase, the distal end of the shaft of a laparoscopic instrument may bepositioned to sequentially engage tissue at each of two or morelocations using releasable tissue engagement mechanisms mounted onretrievable tethers, wherein each tissue engagement mechanism, afterbeing engaged in tissue, is released from the end of the shaft of thelaparoscopic instrument, yet remains connected to the instrument by atether (e.g. a suture, wire, or the like). This allows the instrument tobe moved freely between each desired tissue engagement location todeploy two or more tissue engagement mechanisms at different tissuesites. Subsequently, the tethers may be selectively retrieved, orretracted back toward the shaft of the device to draw the engaged tissuesites toward one another, thereby approximating the tissue sites.Alternatively a cinching member through which the flexible tethers passmay be slid distally down the length of tethers, causing the engagedtissue locations to move toward each other, thereby approximatingtissue. Retrieval of the tether(s) and/or operation of the cinchingmember(s) is under the control of an operator using associated actuationmechanisms.

It will be appreciated that methods and systems of the present inventionmay be used in connection with other diagnostic and therapeutic methodsand devices. Methods of the present invention may thus be used, forexample, in connection with conventional diagnostic and therapeuticmethods and may involve the administration of diagnostic or therapeuticagents, agents for visualizing the interventional site, and the like.Similarly, device components of the present invention may be used inconnection with various procedures and agents that are known in the art.Certain device components that are intended for introduction to theinterventional site, such as tissue engagement mechanisms, probes,extendible members, fasteners, and the like may be administered inassociation with various types of diagnostic or therapeutic agents, ormay be coated or impregnated with such materials. Suitable agents mayinclude clotting agents, healing agents, hydrophobic and/or hydrophilicmaterials, agents promoting lubricity, and the like.

FIGS. 5A-5F illustrate an exemplary tissue approximation deviceaccording to one embodiment of the present invention. An overview ofdevice 500 is shown in FIG. 5A in the pre-deployed configuration, andFIG. 5B shows a distal end of device 500 in the deployed configuration.Device 500 comprises an elongate tubular member 502 having at least oneinternal working channel 504, handle assembly 506 positioned at theproximal end, and approximating tool assembly 508 positioned at thedistal end, wherein approximating tool assembly 508 is shown in thecollapsed (i.e. pre-deployment or fully retracted) state, substantiallyconfined within working channel 504. In the case of minimally invasivelaparoscopic surgery, this low profile collapsed state configuration isuseful for delivery of the instrument to and removal of the instrumentfrom an internal site in the patient, such as the abdominal cavity,through a standard trocar. It is therefore generally desirable that theouter diameter of elongate tubular member 502 be as small as possible,preferably 15 mm or less, more preferably 12 mm or less and, in someembodiments, 5 mm or less. Also shown in FIG. 5A, actuating mechanismssuch as a trigger 510, slider 512, and plunger 514 are provided inconnection with handle assembly 506. Also shown is rotating collar 516that allows the orientation of handle assembly 506 to be independentlyadjusted by the operator relative to the orientation of approximatingtool assembly 508.

FIG. 5B shows an enlarged cross section view of the distal end of device500, with approximating tool assembly 508 being shown in the collapsedstate. In this configuration, located along longitudinal axis 518 ofworking channel 504 are two (or more) extendible members 520, andpushing member 522, each being operatively connected to an actuatingmechanism operated at the handle assembly 506, as described below. Eachof said extendible members 520 is configured at its distal end with atissue engagement mechanism 524 comprising one or more mechanisms forcontrollably and selectively grasping, grabbing, gripping, piercing,holding or otherwise engaging tissue. In the example shown, tissueengagement mechanism 524 incorporates a tissue hook 526. Hook 526 has agenerally pointed distal end for penetration of tissue and has arelatively short curved segment, thus limiting the degree of tissuepenetration. Tissue engagement mechanisms having a generally pointed andsharp tissue penetration structure for penetrating tissue, such as therelatively tough serosal layer forming the exterior gastric wall, arepreferred in many embodiments.

FIG. 5C shows an enlarged view of the distal end of tissue approximationdevice 500, with approximating tool assembly 508 being shown in theextended state, i.e. after being deployed by the operator. In thisembodiment, extendible members 520 open, or extend, along a predefinedpath as they're released from the distal end of the shaft. An actuatingmechanism such as plunger 514 is operatively connected to extendiblemembers 520, such that when plunger 514 is axially displaced into handleassembly 506, extendible members 520 move distally along longitudinalaxis 518 and thereby extend outward from working channel 504 beyond theend of elongate tubular member 502. After deployment to an expandedstate, each of extendible members 520 is positioned with its distal ends524 spaced apart from and positioned on opposite sides of longitudinalaxis 518 from an opposing extendible member.

The degree of extension of the extendible members, and the spacing 521between distal ends 524 of extendible members 520 may be governed by thedegree of deployment out of shaft 502. In some embodiments, both thedegree of extension of distal ends 524 from the shaft 504, indicated aslongitudinal spacing 519, and the distance between extended distal ends524 are selectably controllable by the operator to facilitate tissueengagement at desired locations, and to facilitate the creation of atissue plication of the desired dimensions, thereby producing thedesired gastric volume reduction.

Tissue approximating device 500 illustrated in FIGS. 5A-5F additionallycomprises a pushing member 522 operatively connected to an actuator,such as slider 512, such that when slider 512 is translated away fromits proximal (fully refracted) position, the distal end of pushingmember 522 moves along longitudinal axis 518, thereby extending out ofworking channel 504 a distance 505 beyond the end of elongate tubularmember 502. The extension of pushing member 522 facilitates invaginationof a tissue fold and formation of a tissue plication as two or moretissue sites are approximated. Pushing member 522 may be operatedindependently of, or in coordination with, extendible members 520. Inone embodiment, pushing member 522 is extended out of working channel504 as the extendible members 520 are extended and the tissue engagementmechanisms are positioned to engage tissue.

Illustrative operation of a tissue approximation device 500 illustratedin FIGS. 5A-5F is described below. Following insertion of the shaft intothe intra-abdominal space and positioning of the distal end of the shaftnear a desired tissue approximation site, extendible members 520 aredeployed from a collapsed state to an expanded state to prepare thedevice for subsequent tissue engagement steps. In one embodiment,extendible members 520 are expanded by an actuator that pushes themembers out of, or releases them from the shaft, as follows. In thiscase, extendible members 520 are produced from a highly flexible andelastically deformable material (e.g. flexible polymers, flexiblemetals, shape change materials and combinations thereof may be used) andare made in a shape when in the expanded state having an outward (i.e.away from longitudinal axis 518) curvature. As the extendible members520 are released from the working channel 504, they assume theirexpanded state, and the distal tissue engagement mechanisms are broughtinto contact with the tissue surface. Due to their flexible nature andoutwardly curved shape, extendible members 520 flex elastically andcontinue to assume a progressively more extended condition as theoperator continues releasing them from the shaft, causing distal armportions 524 to slide outward along the tissue surface, becoming spacedapart, until the distal tissue engagement mechanisms are located in thedesired positions for tissue engagement, as described below.

In another embodiment, extendible members 520 are designed to bereleased from the collapsed state to the expanded state in aself-actuating manner, automatically achieving the desired tissueengagement configuration when extended out of working channel 504 beyondthe end of elongate tubular member 502. Such self-actuating motions canbe achieved by various methods known in the art. For example, in onepreferred embodiment of the present invention, extendible members 520are produced from a highly elastic material (e.g. spring steel, hardenedstainless steel, a shape change material such as a superelastic NiTialloy, superelastic polymer, or the like) and are formed duringmanufacturing into the desired final deployed shape by mechanical and/orthermomechanical processing means known in the art. Extendible members520 are then biased (i.e. mechanical potential energy is stored, similarto a pre-loaded spring) by elastically deforming and loading them intoworking channel 504 to thereby provide the device in its collapsedstate. As extendible members 520 are then pushed out of working channel504 during deployment, the stored energy is released and extendiblemembers 520 automatically return to the pre-determined shape desired forsubsequent tissue engagement when brought into contact with the tissuesurface. It will be appreciated that different assemblies of extendiblemembers having different dimensions, different curvatures, differentelastic properties, and the like may be provided for use in a tissueapproximating device of the present invention and an operator may selectan appropriate extendible member assembly having the desired dimensionsand extension properties and install the desired assembly in the workingchannel prior to an intervention.

In yet other embodiments, deployment of extendible members 520 from thecollapsed state to the expanded state may be accomplished, by means ofan actuating mechanism, by any combination of manual pushing to causeexpansion and self-actuating expansion mechanisms. Factors that may beadjusted to optimize the above described reconfiguration and deploymentmotions include, for example, the cross sectional shape, curvatures,mechanical properties, length, etc. of extendible members 520. It shouldalso be obvious to those skilled in the art that, within the scope ofthe present invention, other mechanical actuation mechanisms ofproviding the desired reconfiguration and deployment to adjust theextendible members from the collapsed state to the expanded state mayalso be used. Such actuating mechanisms may comprise, for example,springs, levers, cams, gears, linkages, and the like may be used.

Distal ends 524 of extendible members 520 each incorporate one or moretissue engagement means configured to allow targeted tissue surface 535to be selectively and controllably engaged by the device when actuatedby the operator. Various tissue engagement mechanisms are known in theart may be employed to provide secure and robust tissue engagementhaving sufficient strength, for example, to allow the tissue to besubsequently pulled or otherwise manipulated without disengaging,slipping or tearing. Tissue engagement mechanisms that may be usedinclude, for example, hooks, barbs, grippers, teeth, clamps, jaws,clips, t-tags, and the like. According to one embodiment of the presentinvention, as shown in FIG. 5C, tissue hooks 526 are located at thedistal ends 524, and further comprise sharpened points 528 to promotetissue penetration. While extendible members 520 are in the expandedstate, distal ends 524 and tissue hooks 526 are positioned such thatsharpened points 528 curve slightly downward (distally) and inward(toward longitudinal axis 518). As a result, when pushed slightlydownward onto the surface of the tissue, elastic deformation ofextendible members 520 causes distal ends 524 to first move slightlyoutward. Then, when extendible members 520 are either lifted slightly(e.g. by the surgeon lifting device 500) or alternatively, whenretraction of the extendible members is initiated by the operator (asdescribed below), tissue hooks 526 move slightly downward and inward,thereby causing sharpened points 528 to pierce, penetrate and securelyengage the tissue at tissue engagement locations 530, as shown in FIG.5D. Preferably, distal ends 524, tissue hooks 526 and sharpened points528 are designed such that secure tissue engagement is achieved bypenetrating only the serosal tissue surface 535 (i.e. the serosal tissuelayer), or a combination of the serosal and muscularis tissue layers,without penetrating the mucosal tissue surface 540.

While more complicated mechanical tissue engagement means may beemployed in accordance with the present invention (e.g. hinged jaws,mechanical clamps, forceps, grippers, vacuum actuated mechanisms, andthe like) there are several advantages to the embodiment describedabove, and similarly designed self-actuating embodiments. One advantage,for example, is that it is a simple, single component design having lowproduction cost. Additionally, successful operation of this device isnot particularly dependent upon operator technique (i.e. nosophisticated hand motions or unusual device manipulations arerequired), successful operation instead being more dependent upon devicedesign factors that control, for example, the directions and magnitudesof the forces generated by extendible members 520 during the pushing andpulling motions involved in deployment and/or retraction of the device.Examples of design factors that may be optimized in the self-actuatingdesign embodiments of the present invention include the shape, physicaldimensions, geometrical angles, surface finish, and the like, ofextendible members 520, distal ends 524, tissue hooks 526, and sharpenedpoints 528, as well as their materials of manufacture and mechanicalproperties.

In one embodiment, extendible members 520 have a non-circular, generallyflattened cross section to effectively increase the lateral (i.e. out ofplane) stiffness when extendible members 520 are extended. Examples ofsuitable non-circular cross sectional shapes include square crosssections, rectangular cross sections, triangular cross sections, arcuatecross sections, hemispherical cross sections, oblong or flattenedcross-sections, and combinations of the foregoing. The cross sectionalshape, physical dimensions, mechanical properties, and so on, ofextendible members 520 may be designed having variations along theirlength to provide improved deployment, tissue engagement or retractioncharacteristics.

In another embodiment, extendible members 520 have a pre-determinedshape when in the expanded state that includes at least two bends havingradii of curvature in substantially opposing directions. Such a shape,as illustrated in FIGS. 5C-5E and explained above, may be utilized toinitially give rise to a slight downward motion of distal ends 524, inaddition to the inward motion that occurs during the retraction ofextendible members 520 back into working channel 504, wherein thecombined initial downward and inward motions of distal ends 524effectively promotes tissue penetration and secure tissue engagement ofsharpened points 528 on tissue hooks 526 upon actuated retraction ofextendible members 520. The combined initial downward and inward motionsof distal ends 524 that promote tissue penetration and secure tissueengagement may also be achieved using other designs obvious to thoseskilled in the art. This embodiment simplifies the operation, improvesconsistency, reduces procedural times and risk of complications, byminimizing reliance on individual operator technique and instead takingadvantage of highly controlled and repeatable device motions.

After tissue has been securely engaged by approximating tool assembly508, as described above, the operator actuates device 500 to initiatethe tissue invagination and approximation step, wherein the desiredtissue fold is formed by bringing serosal tissue surfaces between theengaged tissue sites in contact with each other, so that the mucosaltissue surface 540 forms a plication extending into the gastrointestinallumen. FIG. 5E illustrates this process. In the example provided, theoperator selectively activates device 500 remotely using trigger 510provided within handle assembly 506, which is operatively connected toextendible members 520 in a manner such that, as trigger 510 issqueezed, extendible members 520 are thereby controllably retracted andpulled back into working channel 504, as indicated by retraction forces531. The mechanisms used to operatively connect trigger 510 toextendible members 520 may include various mechanical elements known tothose skilled in the art, such as gears, transmissions, levers, pivots,linkages, and the like, whether manual or automated, in order to providethe retraction forces at the working (distal) end of the device, whilekeeping the actuating mechanisms operated by the operator at aconvenient level.

The retraction of extendible members 520 causes tissue engagementlocations 530 to be gradually pulled inward toward longitudinal axis518. In one device embodiment that incorporates a pushing member, theoperator may selectively and independently actuate pushing member 522from within handle assembly 506 (i.e. using slider 512) as the tissueengagement locations are drawn toward one another. The pushing member isextended distally along longitudinal axis 518 to contact and pushagainst the tissue, e.g. with pushing force 532, at a location betweentissue engagement points 530. This promotes tissue invagination in thedesired manner while the engaged tissue is approximated, as shown inFIG. 5E. Once extendible members 520 have been fully retracted bycomplete actuation of trigger 510, the tissue engagement locations 530have been brought into approximation near the distal end of elongatetubular member 502 to create tissue fold 540 as shown in FIG. 5F. Inthis illustration, pushing member 522 is shown remaining in the fullyextended position.

The combination of extendible members and a pushing member in devices ofthe present invention, enabling the combined action of pulling tissueengagement points 530 toward one another via retraction of extendiblemembers 520 while simultaneously having the user selectable option topush against the tissue between tissue engagement points 530 withpushing member 522 promotes creation of a uniform and consistent tissuefold, as shown in FIG. 5F. In preferred embodiments of the presentinvention therefore, operation of the device in the described mannereffectively approximates opposing serosal tissue surfaces 535 inside thetissue fold, providing substantially intimate serosa-to-serosa contact,without forming wrinkles, bunches, gaps, or the like, and withoutpenetrating the mucosal tissue surface 540.

In other embodiments of the present invention, additional userselectable controls may be optionally provided within handle assembly506. For example, controls may be optionally provided to allow thesurgeon to adjust the span 521 of extendible members 520 when in theexpanded state, and the distal extension distance 505 and pushing force532 of pushing member 522. Independent, operator controlled actuationmechanisms may be provided for each of the more than one extendiblemember 520, and the actuation mechanisms may control the speed and forcethat may be used to retract extendible members 520, as well as otheroperating parameters. It should also be recognized that the actuationmeans described above are exemplary, and that other actuation andcontrol mechanisms that are known to those skilled in the art may beused and are considered within the scope of the present invention. Forexample, actuation may be accomplished manually by one or more variousmeans known in the art (e.g. triggers, levers, buttons, knobs, or thelike) or by one or more various powered means known in the art (e.g. ACor DC electric motors, compressed gas, vacuum, or the like), or by anycombination of the foregoing.

As described previously, according to one embodiment of the presentinvention, it is desirable to selectively and therapeutically treat theserosal tissue layer to promote bonding or adhesion of the serosallayers that abut one another within the plication. This may beaccomplished using device 500 in various ways. For example, in oneembodiment illustrated in FIGS. 5C-5F, the distal tip and/or lateralsurfaces of pushing member 522 may be used to mechanically disturb anddisrupt the thin layer of mesothelial cells that form the outermostcovering of the serosa. Since the layer of mesothelial cells coveringthe serosa is quite thin and fragile, it is easily disrupted, andpushing member 522 may be scraped, dragged or otherwise frictionallymoved across the surface of the tissue to produce the desireddisruption. To further aid in disrupting the serosal tissue surface andpromote tissue adhesion, pushing member 522 may be modified, forexample, by incorporating roughening features 523, illustrated asprotuberances in FIGS. 5C-5F. As will be obvious to those skilled in theart, a wide variety of such roughening features and arrangements may beused to accomplish the desired serosal treatment, for example, ridges,bumps, bristles, teeth, scales, serrations, and the like may be used.

The optional serosal treatment described above may be carried out beforethe tissue fold is formed, after the tissue fold is formed but prior tothe securing means is applied, after the tissue fold is formed and thesecuring means is applied, or any combination of the foregoing. Forexample, prior to actuating extendible members 520 to engage tissue, thedistal end of pushing member 522 may be moved across substantially theidentified area of serosal tissue to be included within the tissue foldin a sweeping or painting type of motion. Alternatively, the lateralsurfaces of pushing member 522 contact and slide across the opposingserosal tissue surfaces of the tissue fold when pushing member 522 isretracted from within the tissue fold (as is evident in FIG. 5F),thereby disrupting at least a substantial portion of the serosal tissuesurface during normal device operation. In this case, rougheningfeatures 523 present on the lateral surfaces of pushing member 522 mayensure more uniform and consistent serosal treatment, leading to a moreeffective and stronger serosa-to-serosa tissue bond.

In another serosal treatment embodiment, ports may be provided near thedistal tip of shaft 502 and/or along pushing member 522 such that, whenthe shaft and/or pushing member lumen is connected to a supply of sourcematerial (e.g., a liquid reservoir located within or attached to theproximal handle assembly 506), the device provides controlled dispensingof a chemical or therapeutic agent (e.g. liquid, gas, solid powder,solid film, or combinations thereof) onto the tissue surface thatpromotes tissue bonding and adhesion. Alternatively, the distal tip ofshaft 502 and/or pushing member 522 may optionally incorporate an energydeposition mechanism capable of delivering energy to the target tissue.Exemplary energy deposition mechanisms include, for example, componentscapable of RF cauterizing, electro-cauterizing, ultrasonic vibration,and the like.

According to the present invention, once the tissue has beenapproximated and the desired tissue fold has been created as describedabove, fasteners are then applied to secure the plication. This is mostconveniently accomplished while approximating tool assembly 508 is heldin place by the operator to maintain the tissue in a stable, foldedconfiguration. In one embodiment, a separate interventional instrumentmay be introduced through a separate trocar, and its distal tip may bepositioned immediately adjacent approximating tool assembly 508. Thisinstrument is then actuated to apply a fastener directly into and acrossthe shoulders of the approximated tissue forming the tissue fold,thereby securing the plication. In this embodiment illustrated in FIG.6A, a system 600 of the present invention comprises two separatehandheld devices, each device capable of being actuated using controlslocated at their respective proximal handle assemblies. A first device620 incorporates an approximating tool assembly 625 which may besubstantially similar to approximating tool assembly 508, describedabove, at its distal end, and a second device 640 incorporates afastening tool assembly 645 at its distal end, capable of applying afastener to the tissue fold to secure the plication. A wide variety of asuitable fasteners are known to those skilled in the art and may besuitably be used as fasteners within the broad scope of the presentinvention. Exemplary fasteners comprise, for example, sutures, box-typestaples, U-shaped or hemispherical fasteners, helical fasteners, clips,tacks, wall anchors, t-tags, and the like. A commercially availablelaparoscopic stapler, suturing device or tack applicator may be used tosecure the tissue fold.

Accordingly, the laparoscopic interventional stapler shown in FIG. 6Acomprises an elongate tubular shaft 650 having at its proximal end ahandle assembly 655 containing user controls, actuation mechanisms, andso on, and having at its distal end a fastening tool assembly 645, whichincorporates mechanisms known in the art for feeding, deploying, formingand applying to the target tissue a plurality of fasteners. Thesefasteners are most commonly made from stainless steel, titanium or NiTi,although other materials may also be used (e.g. other biocompatiblealloys, polymers, bioabsorbable materials, and the like). Typically, aplurality of such staples would be provided within a disposable (i.e.single patient use) cartridge that is loaded at the distal end of thedevice, allowing multiple staples to be placed consecutively by theoperator without removing the device from the patient.

FIG. 6B shows a close up view of the distal ends of device 620 anddevice 640, indicating the preferred relative positioning ofapproximating tool assembly 625 and fastening tool assembly 645,respectively, according to one embodiment of the present invention. Inthis view, approximating tool assembly 625 has previously been deployed,the tissue has been engaged, and the extendible members have beenretracted (these steps being carried out e.g. as described in FIG. 5),in order to create tissue fold 660. Shoulders 665 of tissue fold 660 areapproximated near the distal tip of approximating tool assembly 625, andare held in position, ready for the tissue fastener to be applied byfastening tool assembly 645. The cross sectional view of FIG. 6C shows aclose up of the distal tip of fastening tool assembly 645. In thisexample, a box-type staple in the pre-deployed state 670 is shown loadedwithin the within fastening tool assembly 645. Prior to applying thestaple, fastening tool assembly 645 is positioned such that staple legs671 of box-type staple in pre-deployed state 670 are positionedsubstantially perpendicular to, and in contact with, shoulders 665 ofthe tissue fold. When the surgeon fires the stapler using actuationmeans provided within the proximal handle assembly, extendible pistons642 extend distally, deforming staple legs 671 around stationary anvil644 and thereby reconfiguring the box-type staple into deployed state675 as it is ejected from the device. As the staple is deployed, itpenetrates the tissue and simultaneously pulls opposing tissue shoulders665 toward one another, as shown. Note in this example that the box-typestaple in deployed state 675 engages only the outermost layers ofgastric tissue, i.e. serosal layer 535 and/or the muscularis tissuelayers (not shown), and that there is no penetration through the gastricwall, which preserves the mucosal tissue layer 540 intact. FIG. 6Dschematically illustrates a plication being secured using severalconsecutively repeated applications of the above described procedure.Approximating tool assembly 625 and fastening tool assembly 645 areshown, along with a multiplicity of individual box-type staples in thedeployed state 675 that have been applied and which are arranged in asubstantially continuous row extending along the length of tissueshoulders 665 to secure plication 690 projecting into thegastrointestinal space. The depth 680 below the surface and spacing 685between the individual staple placements may be selectively controlledby the operator.

In another embodiment of the present invention, the tissue approximatingand fastening functions described above requiring the use of twoseparately operable handheld interventional instruments are combinedinto a single multi-functional device having one or more integratedtools capable of invaginating and approximating tissue to create atissue fold, as well as one or more integrated tools for applyingfasteners to secure the plication. By combining these functionsconveniently in a single handheld device, the overall procedure issimplified, and it can be performed without requiring extensive operatortraining Furthermore, the need for one laparoscopic access port iseliminated, which provides a significant advantage.

FIGS. 7A-7H illustrates such an integrated device and its operation,according to one embodiment of the present invention. Device 700comprises an elongate tubular member 702 having internal working channel704 and handle assembly 706 positioned at the proximal end. At thedistal end of device 700 is multi-functional tool assembly 708, shown inthe collapsed (i.e. pre-deployment or fully retracted) state in FIG. 7A.It is generally desirable that the outer diameter of elongate tubularmember 702 be as small as possible, preferably 20 mm or less, morepreferably 15 mm or less and, in some embodiments, 12 mm or less. Theembodiment illustrated in FIG. 7A, illustrates actuating mechanisms usedto operate the device, namely first trigger 710, second trigger 711,slider 712, and plunger 714 provided in connection with handle assembly706. Also shown is rotating collar 716 that allows the orientation ofhandle assembly 706 to be independently adjusted by the user relative tothe orientation of approximating tool assembly 708.

A close up cross sectional view of the distal end of device 700 is shownin FIG. 7B, illustrating details of multi-functional tool assembly 708in the collapsed state. Multi-functional tool assembly 708 combinessubstantially similar structural and functional elements as previouslyillustrated in and described with reference to FIGS. 5 and 6.Accordingly, in this configuration, located along longitudinal axis 718of working channel 704 are two (or more) extendible members 720, and(optional) pushing member 722, each being operatively connected toactuating mechanisms accessible to an operator at handle assembly 706.Each of the extendible members 720 is configured at its distal end witha distal tip 724, and each distal tip 724 incorporates one or moretissue engagement mechanisms whose working function is to controllablyand selectively grasp, grab, grip, pierce, hold or otherwise engagetissue. In the example shown, distal tips 724 incorporate tissue hooks726. Box-type staples in pre-deployed state 730 are loaded into workingchannel 704 and are configured (using, for example, guide channels and aspring loading mechanism) to slidably move toward the distal end ofmulti-functional tool assembly 708 and into the pre-fire position 731 asstaples are sequentially ejected from the device. Pistons 732 arepositioned at the distal end of shaft 733, and, along with stationaryanvil 734, are used to deform staple legs 735 and thereby reconfigureand eject the staples when the device is actuated by the user, asdescribed below.

FIG. 7C illustrates a close up view of multi-functional tool assembly708 having extendible members and tissue engagement mechanisms in theextended state, i.e. after being deployed by the operator. In theembodiment illustrated, plunger 714 is operatively connected toextendible members 720, such that when plunger 714 is pushed into handleassembly 706, extendible members 720 move distally along longitudinalaxis 718 and thereby extend outwardly from working channel 704 andbeyond the end of elongate tubular member 702. During deployment to theextended state, each of extendible members 720 is positioned such thatdistal tips 724 are spaced apart from one another and positioned onopposite sides of longitudinal axis 718. In the example shown,extendible members 720 have a flattened cross sectional configuration toincrease lateral stiffness and prevent undesirable out-of-plane bendingduring deployment. Distal tips 724 of the extendible members 720 maycomprise multiple tissue hooks 726, which facilitate secure tissueengagement and help to prevent undesired out-of-plane bending ofextendible members 720 during deployment. Both the longitudinalpositioning 719 and spacing 721 of arm tips 724 may be selectablycontrolled by the user to facilitate the desired positioning of tissueengagement members 726 and the subsequent size and position of thetissue plication formed by approximating the tissue.

Device 708 additionally incorporates pushing member 722, which isoperatively connected to slider 712, such that when slider 712 is pushedfrom its proximal (fully retracted) position, the distal end of pushingmember 720 moves along longitudinal axis 718, thereby extending out ofworking channel 704 a user selectable distance 705 beyond the end ofelongate tubular member 702. The pushing member facilitates invaginationand folding of the tissue between the engaged portions and may,additionally, function to disrupt the serosal tissue surface, orfacilitate application of a tissue bonding promoter, as described above.Operation of the pushing member may be independent of, or coordinatedwith, extension and retraction of the extendible members and tissueengagement mechanisms.

The steps of deploying device 700, engaging tissue, and invaginating andapproximating tissue to create a tissue fold are substantially similarto what was previously described with reference to FIGS. 5D-5F. For thesake of clarity, these sequential steps are again illustrated in FIGS.7D-7F with reference to operation of multi-functional tool assembly 708.After the tissue has been approximated and the fold has been created,device 700 is positioned in a suitable location for the subsequent stepof applying one or more fasteners to secure the plication. Accordingly,similar to corresponding FIG. 6C, FIG. 7G illustrates the distal portionof device 700 after the device has been actuated from within handleassembly 706 using a second trigger 711, which is operatively connectedto extendible shaft 733. The actuation, as described previously, formsand ejects a box-type staple, reconfiguring it by deformation from thepre-deployed state 730 to the deployed state 736, and securelyimplanting the staple within the tissue as described previously. Thisresults in penetration and pulling together of the opposing tissueshoulders 765, which thereby secures the created tissue plication 790projecting into the gastrointestinal space. Tissue hooks 726 may then beoperatively disengaged from the tissue using a slight forward actuationof plunger 714 located within handle assembly 706, after whichextendible members 720 may be completely retracted back into the shaftof the device by full reverse actuation of plunger 714. Pushing member722 may also be completely retracted back into the device, using reverseactuation of slider 712. The serosal tissue layer may be treated topromote bonding during manipulation of the pushing member, as discussedpreviously. The next in line pre-loaded staple in the pre-deployed state730 automatically (for example, via spring pressure) moves into thepre-fire position 731, and the device is therefore fully prepared andready for repeating the entire sequence at the next tissue locationselected by the operator, as shown in FIG. 7G.

As illustrated in FIG. 7H (substantially similar to FIG. 6D), afterrepeating the procedural steps described above using multi-functionaltool assembly 708, a plurality of staples in the deployed state 736 areimplanted into and across tissue shoulders 765, securing plication 790projecting into the gastrointestinal space. One or more such plicationsmay be produced in this manner, each having the desired length, depth,etc., and each having a selectable number of implanted fasteners,fastener depth, fastener-to-fastener spacing, and so on, as previouslydescribed. Using the devices of the present invention in this manner,the operator is therefore able to achieve the desired gastric reductionlaparoscopically and without ever needing to fully penetrate the gastricwall or otherwise compromise the internal mucosal tissue layer.

FIG. 8A illustrates a close up view of the distal end of a tissueapproximation device according to another embodiment of the presentinvention. In this case, the device is a handheld instrument that isdesigned and operates similarly to device 700, and incorporatesmulti-functional tool assembly 808 at a distal end of the shaft.Multi-functional tool assembly 808 is similar to multi-functional toolassembly 708 described above, with the notable exception that thefasteners used in this embodiment are helical fasteners, shown ashelical fastener 810 in FIG. 8A, as an alternative to the box-typestaple described previously. Helical fastener 810 may be formed fromwire having desirable characteristics (e.g. strength, stiffness, surfacefinish, anti-friction coatings, drug eluting coatings, and so on) and,as shown in FIG. 8B, includes body 812, sharpened leading tip 814 andproximal end 816. Fastener body 812 may have one or more screw- orcoil-type turns, and is additionally characterized by length 818 anddiameter 820, which may be optimized according to the desired depth andwidth of tissue penetration desired for various interventionalprocedures. Length 818 is preferably between 1 mm and 50 mm, morepreferably between 2 mm and 40 mm and, in many embodiments, between 3 mmand 30 mm. Diameter 820 is preferably between 1 mm and 20 mm, morepreferably between 2 mm and 15 mm and, in many embodiments, between 3 mmand 12 mm. Sharpened tip 814 is configured to aid in tissue penetrationduring deployment. Proximal end 816 is typically configured to allowoperative engagement directly or indirectly to a rotating shaft locatedwithin the working channel of the elongate tubular member of device 800,such that when rotatingly actuated from within the handle assembly, thehelical fastener rotates as it exits the distal end of the device,thereby penetrating the tissue. Helical fastener 810 may be fabricatedfrom any suitable biocompatible material known in the art, for examplestainless steel, Ti, NiTi, or the like may be used, as well as othermaterials such as polymers, ceramics, and combinations of the foregoing.

In using the device illustrated in FIGS. 8A-8E, the steps of deployingthe device, engaging tissue and approximating tissue to create a tissuefold are substantially identical to what was described above regardingdevice 700, and illustrated in FIGS. 7A-7H. After the tissue fold hasbeen created, multi-functional tool assembly 808 is in position andready to apply the securing means, as illustrated on FIG. 8C. FIG. 8Dshows multi-functional tool assembly 808 immediately after helicalfastener 810 has been applied to the tissue fold to produce plication830, illustrating the preferred placement location and orientation ofhelical fastener 810 between tissue shoulders 840. It is important thatdiameter 820 of helical fastener 810 be sized appropriately relative tothe thickness of the tissue, and that proper orientation of the deviceis maintained (i.e. substantially perpendicular to the tissue surfaceand co-planar with the opposing tissue surfaces within the tissue fold),such that tissue on both sides of the tissue fold are repeatedly andconsistently engaged as the helical fastener is deployed into the tissueduring actuated rotation of device 800. Preferably, diameter 820 isapproximately comparable to tissue thickness 850, more preferably it isbetween 0.5× and 1.5× tissue thickness 850, but in any case it is mostpreferably maintained at less than twice the tissue thickness 850 toavoid penetration completely through the stomach wall. Similar to FIG.7H, FIG. 8E shows plication 830 projecting into the gastrointestinalspace that was produced as a result of the repeated placement of device800 and actuation of multi-functional tool assembly 808, wherein aplurality of helical fasteners 810 have been applied, as describedpreviously.

There are advantages to using helical fasteners as securing means inmethods and devices of the present invention. The mechanismsincorporated into devices for loading, feeding and deploying helicalfasteners into the target tissue are simple to construct (e.g. fewmoving parts), compact, reliable, and easy to use. In general, helicalfasteners require only rotation for deployment, and they don'tnecessarily involve reconfiguration from a pre-deployed state to adeployed state, as in the case of spring-type or deforming-typefasteners. Also, helical fasteners may be deployed such that thefastener repeatedly engages tissue at multiple points of contact over arelatively large surface area on the opposing tissue surfaces. Thisleads to effective load distribution and tends to reduce the maximumforces generated on both the tissue and fastener, resulting in lesslikelihood that either the tissue or the fasteners will fail. The use ofhelical fasteners may thus increase the mechanical robustness of theplication produced and improve the long-term prognosis for a successfulinterventional outcome.

In certain situations, it may be desirable and advantageous to(optionally) provide additional reinforcement to the opposing tissuesurfaces within the tissue fold and resulting plication. Such additionalreinforcement not only results in stronger securement of the plicationand greater load distribution, but it may also provide stabilizationagainst undesirable or excessive tissue motions, more intimateserosa-to-serosa contact and bonding, and increased rigidity to thegastrointestinal lumen (which may reduce the amount of stretching thatoccurs during digestion. Additional reinforcement may be accomplishedusing the methods and devices of the present invention by applyingadditional fasteners at a location within the plication as it is beingproduced, as illustrated in FIGS. 9A and 9B. FIG. 9A illustrates thatmulti-functional tool assembly 808 has been used to place first helicalfastener 910, creating first plication 920 having depth 925, using theprocedures described previously. Next, rather than move to the nexttissue location to repeat the procedure (e.g. as shown in FIG. 8D),multi-functional tool assembly 808 is instead maintained atsubstantially the same tissue location and tissue approximation isrepeated a second time, creating a second tissue fold directly over topof the initial plication. As shown in FIG. 9B, a second helical fastener930 is then applied, thereby producing extended plication 940 havingdepth 945 (greater than depth 925), and having first helical fastener910 completely inside the plication, acting as an additional securingmeans interior to the plication. This procedure may be repeated as manytimes as desired by the operator, resulting in the successive placementof interior fasteners and extension of the depth of the plication.Beyond the stated benefits of the additional interior fasteners, asignificant advantage of building up the plication depth in this manneris that the maximum designed working span of the device (e.g. spacing721 of arm tips 724 in FIG. 7C) may be reduced, resulting in a morecompact and reliably operating device.

As will be obvious to those skilled in the art, the concept of providingadditional reinforcement to a plication through placement of interiorsecuring means can be extended according to other embodiments of thepresent invention. For example, FIG. 10A illustrates a multifunctionaltool for placing helical fasteners and FIG. 10B illustrates a crosssectional view of a laparoscopically produced plication 1010 projectinginto the gastrointestinal space that was created entirelyextragastrically using multi-functional tool assembly 808. A pluralityof helical fasteners 810 have been placed at various locations along thelength and depth of the plication, thereby ensuring substantiallyintimate serosa-to-serosa contact over substantially the entire tissuecontact area inside the plication. In addition, using the devices of thepresent invention, the surgeon has complete flexibility while performingthe procedure to accommodate natural patient-to-patient anatomicalvariations in organ shape, tissue thickness, texture, presence ofdefects, and the like.

In another embodiment of the present invention illustrated in FIG. 11,device 1100 is substantially similar in many functional aspects to thepreviously described devices. Device 1100 has elongate tubular member1102 having handle assembly 1106 at its proximal end andmulti-functional tool assembly 1108 at its distal end. Handle assembly1106 further comprises the various actuating means that are operativelyconnected to and useful for controlling the extendible elements ofmulti-functional tool assembly 1108, namely first trigger 1110 (used foractuating retraction of extendible members), second trigger 1112 (usedfor actuating deployment of fasteners), slider 1114 (used for actuatingthe pushing member), and plunger 1116 (used for actuating deployment ofthe extendible members). Rotating collar 1118 permits handle assembly1106 to pivot around the longitudinal axis 1120 of elongate tubularmember 1102 in a user selectable fashion.

In device 1100, at least one multi-functional tool assembly 1108 isoperatively connected to the distal end of elongate tubular member 1102at articulating joint 1122. Articulating joint 1122 incorporates aflexible coupling along elongate tubular member 1102, as well asflexible internal components that operatively connect the actuatingmechanisms of handle assembly 1106 to multi-functional tool assembly1108. This feature allows multi-functional tool assembly 1108 to beadjustably positioned by the user at tip angle 1124 relative tolongitudinal axis 1120, as shown. Preferably, tip angle 1124 isadjustable between 0 and ±90 degrees and, in some embodiments, tip angle1124 is adjustable between 0 and ±60 degrees, while in yet otherembodiments, tip angle 1124 is adjustable between 0 and ±45 degrees. Anytype of articulating joint design know to those skilled in the art maybe used, e.g. hinge joints, ball joints, universal joints, bellowsjoints, and the like, may be used. In the example shown, articulatingjoint 1122 allows multi-functional tool assembly 1108 to pivot around asingle axis perpendicular to longitudinal axis 1120, meaning that tipangle 1124 can be adjusted only within a fixed plane. For convenience,in FIG. 11 this is shown as the plane of handle assembly 1106; however,since handle assembly 1106 can rotate around longitudinal axis 1120 (byadjusting rotating collar 1118), the operator has complete relationalcontrol between handle position and distal tip orientation, which isextremely useful for rapid, safe and efficient device operation While asingle articulating joint and multifunctional tool assembly isillustrated in FIG. 11, it will be appreciated that multiplemultifunctional tool assemblies and multiple articulating joints may beprovided in interventional tools of the present invention.

It will be appreciated that while methods and devices of the presentinvention have been described specifically with reference to reducinggastric volume by invaginating and approximating a wall of thegastrointestinal tract to create at least one plication therein, thereare many other applications for both methods and devices of the presentinvention. More generally, methods and devices of the present inventionmay be used to approximate and, optionally, fasten two tissue locations,and may be used in connection with a wide variety of tissue sites, andall of these applications are encompassed by the methods and devices ofthe present invention.

1. A method for reducing gastric volume comprising: accessing anexternal surface of a wall of the gastrointestinal tract at a firstlocation; positioning a distal end of at least one device in proximityto the first location; manipulating a first tissue engagement mechanismof said device to engage tissue by piercing the external surface of thewall of the gastrointestinal tract at a first tissue site andmanipulating a second tissue engagement mechanism of said device toengage tissue by piercing the external surface of the wall of thegastrointestinal tract at a second tissue site spaced apart from thefirst tissue site; manipulating said device while the first and secondtissue sites are both engaged to approximate said engaged, spaced aparttissue sites to create at least one invaginated tissue fold extendingfrom the approximated tissue sites into an interior space of thegastrointestinal tract; and fastening the approximated tissue sites toone another to secure the tissue fold.
 2. The method of claim 1 whereinthe step of fastening the approximated tissue sites to one another tosecure the tissue fold comprises operating said device to fasten theapproximated tissue sites to one another to secure the tissue fold. 3.The method of claim 1, further comprising: repositioning the device to asecond location in proximity to the external surface of the wall of thegastrointestinal tract spaced apart from the first location;manipulating said device at the second location to engage tissue at athird tissue site and at a fourth tissue site spaced apart from thethird tissue site; approximating said engaged third and fourth tissuesites; and fastening the approximated third and fourth tissue sites toone another.
 4. The method of claim 1, further comprising: repositioningthe device to a second location in proximity to the external surface ofthe wall of the gastrointestinal tract spaced apart from the firstlocation; manipulating said device at the second location to engagetissue at a third tissue site and at a fourth tissue site, the third andfourth tissue sites being spaced apart from one another and beinglocated on opposite sides of the tissue fold; approximating the thirdand fourth tissue sites to form an extension of the tissue fold; andfastening the approximated third and fourth tissue sites to one anotherto secure the extension of the fold.
 5. The method of claim 1, whereinthe tissue within said at least one tissue fold is arranged to providesubstantially intimate serosa to serosa contact along at least a portionof tissue within the tissue fold.
 6. A method for reducing gastricvolume comprising, sequentially: accessing an external surface of a wallof the gastrointestinal tract through a laparoscopic incision in theabdominal wall; positioning at least one device in proximity to theexternal surface of the wall of the gastrointestinal tract; operatingthe device to engage at least two spaced apart tissue sites on theexternal surface of the wall of the gastrointestinal tract by piercingat least the external surface of the wall of the gastrointestinal tractat each of the tissue sites; operating the device to approximate theengaged, spaced apart tissue sites while the tissue sites are bothengaged to create at least one invaginated tissue fold extending into aninternal gastric space; and applying a fastener to fasten theapproximated tissue sites to one another to secure the tissue fold,thereby creating at least one plication extending into the internalgastric space of the gastrointestinal tract, wherein the fastener isselected from the group consisting of: sutures, staples, screws, tacks,clips, hooks, clamps, t-tags, and helical fasteners, and combinations ofthe foregoing.
 7. The method of claim 6, wherein approximating thetissue sites involves moving at least one engaged tissue site towardanother tissue site using a type of motion selected from the groupconsisting of pulling motions, pushing motions, twisting motions,shearing motions, and combinations of the foregoing.
 8. The method ofclaim 6, wherein approximating the tissue sites involves moving at leastone engaged tissue site toward another tissue site using a pullingmotion and moving tissue between the tissue sites using a pushingmotion.
 9. The method of claim 8, wherein said pulling motion and saidpushing motion are performed sequentially.
 10. The method of claim 8wherein said pulling motion and said pushing motion are performedsimultaneously.
 11. The method of claim 6, wherein the external surfaceof a wall of the gastrointestinal tract is a portion of the externalsurface of the stomach.
 12. The method of claim 6, additionallycomprising dissecting at least a portion of the omentum to expose theexternal surface of the gastrointestinal tract.
 13. The method of eitherclaim 1 or claim 6, wherein the external surface of a wall of thegastrointestinal tract is selected from the group consisting of: theanterior surface of the stomach, the posterior surface of the stomach,and a combination of both the anterior and posterior surfaces of thestomach.
 14. The method of either claim 1 or claim 6, wherein thegastrointestinal tract is the stomach and the tissue fold decreases thefunctional volume of the stomach by at least 20%.
 15. A method forreducing gastric volume comprising: accessing an external surface of awall of the stomach and positioning at least one device in proximity tothe external surface of the wall of the stomach; manipulating a firsttissue engagement mechanism of the device to pierce the external surfaceof the stomach to engage a first tissue site and manipulating a secondtissue engagement mechanism of the device to pierce the external surfaceof the stomach to engage a second tissue site spaced apart from thefirst tissue site; manipulating tissue at the engaged first and secondtissue sites to approximate the first and second tissue sites by movingthe first and second tissue sites toward one another to form aninvaginated tissue fold extending into an internal gastric space anddecreasing a functional volume of the stomach by at least 20%; andfastening tissue in proximity to the approximated first and secondtissue sites to secure the tissue fold, thereby creating at least oneplication extending into the internal gastric space.
 16. A method forreducing gastric volume comprising: accessing an external surface of awall of the stomach; engaging the external surface of the stomach at afirst tissue site using a first tissue hook having a sharpened point andengaging the external surface of the stomach at a second tissue sitespaced apart from the first tissue site using a second tissue hookhaving a sharpened point; manipulating tissue at the engaged first orsecond tissue sites to approximate the first and second tissue sites toform an invaginated tissue fold extending into an internal gastric spaceand decreasing a functional volume of the stomach by at least 20%; andfastening tissue in proximity to the approximated first and secondtissue sites to secure the tissue fold, thereby creating at least oneplication extending into the internal gastric space.
 17. The method ofclaim 16, further comprising manipulating tissue at the first tissuesite or second tissue site to approximate the first and second tissuesites by moving at least one engaged tissue site toward another tissuesite.
 18. The method of either claim 15 or claim 16, comprisingfastening tissue by application of at least one fastener selected fromthe group consisting of: sutures, staples, screws, tacks, clips, hooks,clamps, t-tags, and helical fasteners, and combinations of theforegoing.
 19. The method of either claim 15 or claim 16, additionallycomprising engaging, approximating and fastening tissue by penetratingat least the serosal layer while penetrating fewer than all of thelayers of the wall of the stomach.
 20. The method of either claim 15 orclaim 16, additionally comprising treating at least a portion of theexternal surface of the stomach to promote serosa to serosa bondingwithin the plication.
 21. The method of claim 20, wherein the treatmentis selected from the group consisting of physically disrupting thetissue surface, administering an agent to the tissue surface, orapplying energy to the tissue surface, and combinations of theforegoing.
 22. The method of either claim 15 or claim 16, whereinforming and securing the invaginated tissue fold produces contacting ofat least a portion of the tissue surfaces within said at least oneplication, thereby providing substantially intimate serosa to serosacontact of at least a portion of the tissue surfaces within said atleast one plication.
 23. The method of either claim 15 or claim 16,wherein the plication decreases the functional volume of the stomach byat least 30%.
 24. The method of either claim 15 or claim 16, wherein theplication decreases the functional volume of the stomach by at least40%.
 25. The method of either claim 15 or claim 16, wherein theplication decreases the functional volume of the stomach by at least50%.
 26. The method of either claim 15 or claim 16, additionallycomprising dissecting at least a portion of the omentum to expose theexternal surface of the stomach.
 27. The method of either claim 15 orclaim 16, wherein the external surface of the stomach is selected fromthe group consisting of the anterior surface of the stomach, theposterior surface of the stomach, and a combination of both the anteriorand posterior surfaces of the stomach.
 28. The method of either claim 15or claim 16, wherein staples are applied to secure the tissue fold, andthe staples grasp tissue shoulders formed where opposing layers of thetissue fold intersect a circumference of the stomach.
 29. The method ofclaim 28, wherein the staples engage the tissue shoulders by penetratingthrough a serosal tissue layer and into an underlying muscularis tissuelayer, without penetrating completely through the wall of the stomach.30. The method of any one of claims 1, 6, 15 and 16, wherein the tissuefold is in the stomach and extends approximately longitudinally fromnear the fundus to near the pylorus.
 31. The method of any one of claims1, 6, 15 and 16, wherein securing the tissue fold involves placing a rowof individual staples substantially along a length of the fold.
 32. Themethod of any one of claims 1, 6, 15 and 16, additionally comprisingvisually identifying and indicating a target position, a length of thefold centerline and a location of hounding lines where tissue will becontacted prior to engaging the external surface.